webrtc/modules/video_coding/generic_decoder.h

/*
 *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef WEBRTC_MODULES_VIDEO_CODING_GENERIC_DECODER_H_
#define WEBRTC_MODULES_VIDEO_CODING_GENERIC_DECODER_H_

#include <memory>

#include "webrtc/base/thread_checker.h"
#include "webrtc/modules/include/module_common_types.h"
#include "webrtc/modules/video_coding/encoded_frame.h"
#include "webrtc/modules/video_coding/include/video_codec_interface.h"
#include "webrtc/modules/video_coding/timestamp_map.h"
#include "webrtc/modules/video_coding/timing.h"

namespace webrtc {

class VCMReceiveCallback;

enum { kDecoderFrameMemoryLength = 10 };

struct VCMFrameInformation {
  int64_t renderTimeMs;
  int64_t decodeStartTimeMs;
  void* userData;
  VideoRotation rotation;
};

class VCMDecodedFrameCallback : public DecodedImageCallback {
 public:
  VCMDecodedFrameCallback(VCMTiming* timing, Clock* clock);
  ~VCMDecodedFrameCallback() override;

  void SetUserReceiveCallback(VCMReceiveCallback* receiveCallback);
  VCMReceiveCallback* UserReceiveCallback();

  int32_t Decoded(VideoFrame& decodedImage) override;
  int32_t Decoded(VideoFrame& decodedImage, int64_t decode_time_ms) override;
  void Decoded(VideoFrame& decodedImage,
               rtc::Optional<int32_t> decode_time_ms,
               rtc::Optional<uint8_t> qp) override;
  int32_t ReceivedDecodedReferenceFrame(const uint64_t pictureId) override;
  int32_t ReceivedDecodedFrame(const uint64_t pictureId) override;

  uint64_t LastReceivedPictureID() const;
  void OnDecoderImplementationName(const char* implementation_name);

  void Map(uint32_t timestamp, VCMFrameInformation* frameInfo);
  int32_t Pop(uint32_t timestamp);

 private:
  rtc::ThreadChecker construction_thread_;
  rtc::ThreadChecker decoder_thread_;
  Clock* const _clock;
  // This callback must be set before the decoder thread starts running
  // and must only be unset when external threads (e.g decoder thread)
  // have been stopped. Due to that, the variable should regarded as const
  // while there are more than one threads involved, it must be set
  // from the same thread, and therfore a lock is not required to access it.
  VCMReceiveCallback* _receiveCallback = nullptr;
  VCMTiming* _timing ACCESS_ON(decoder_thread_);
  VCMTimestampMap _timestampMap ACCESS_ON(decoder_thread_);
  uint64_t _lastReceivedPictureID ACCESS_ON(decoder_thread_);
};

class VCMGenericDecoder {
 public:
  explicit VCMGenericDecoder(VideoDecoder* decoder, bool isExternal = false);
  ~VCMGenericDecoder();

  /**
  * Initialize the decoder with the information from the VideoCodec
  */
  int32_t InitDecode(const VideoCodec* settings, int32_t numberOfCores);

  /**
  * Decode to a raw I420 frame,
  *
  * inputVideoBuffer reference to encoded video frame
  */
  int32_t Decode(const VCMEncodedFrame& inputFrame, int64_t nowMs);

  /**
  * Set decode callback. Deregistering while decoding is illegal.
  */
  int32_t RegisterDecodeCompleteCallback(VCMDecodedFrameCallback* callback);

  bool PrefersLateDecoding() const;

#if defined(WEBRTC_ANDROID)
  // See https://bugs.chromium.org/p/webrtc/issues/detail?id=7361
  void PollDecodedFrames();
#endif

  bool IsSameDecoder(VideoDecoder* decoder) const {
    return decoder_.get() == decoder;
  }

 private:
  rtc::ThreadChecker decoder_thread_;
  VCMDecodedFrameCallback* _callback ACCESS_ON(decoder_thread_);
  VCMFrameInformation _frameInfos[kDecoderFrameMemoryLength] ACCESS_ON(
      decoder_thread_);
  uint32_t _nextFrameInfoIdx ACCESS_ON(decoder_thread_);
  std::unique_ptr<VideoDecoder> decoder_;
  VideoCodecType _codecType ACCESS_ON(decoder_thread_);
  const bool _isExternal;
};

}  // namespace webrtc

#endif  // WEBRTC_MODULES_VIDEO_CODING_GENERIC_DECODER_H_